The invention relates to an interactive device for data input into an instrument of small dimensions comprising at least one manually actuated sensor, a control display unit and electronic conversion, memorization and decoding means.
The principal problem which is encountered with a manually actuated data input device intended for an instrument of small dimensions, e.g. for an electrode watch, is the small number of sensor elements (keys or transducers) that can be resolved or actuated individually with one finger only. This small number of sensor elements limits the effective size of an alphanumeric group (hereinafter referred to as an alphabet) which is directly accessible.
The prior art, as indicated below, shows that all data input devices need an additional element in order to be used practically. The additional element may be the instructions for use that the user must assimilate in order to utilize the device efficiently (e.g.: written data input) or a set of indications associated with the input elements like inscriptions written on keys, for example.
U.S. Pat. No. 3,803,834 discloses a wristwatch provided with a calculator having keys for data input and for the selection of the functions, each key being marked with the corresponding cipher or symbol. Such miniature keyboards cannot be actuated by one finger and a stylus is required to actuate the individual keys.
U.S. Pat. No. 3,757,322 shows translucent keys under which a display is provided in order to display the symbol corresponding to the key. The keys which are grouped in a keyboard may be considered as multifunction keys because it is foreseen to change the keyboard, e.g. to change from letters to ciphers, and so on.
Swiss Pat. No. 533 332 shows a system provided with a display to sequentially display the data as it is delivered by a circuit intended to this end, the system containing a control element which permits entry of the desired information. Such a system requires only a small number of keys but is slow in operation.
U.S. Pat. No. 3,309,785 shows a writing area where symbols may be written. The area is provided with sensors which react to the passage of one finger or one pencil. The order of passages being considered, the area produces a sequence of signals from which a circuit recognizes the symbol and controls the display of it. The user of such a device must undergo an apprentiship to learn how to write the symbols in the right way.
The DAS No. 2 235 620 shows an interacting display having a writing area provided with 14 sensor elements and a display with 14 segments which are disposed without any relation to the writing of the symbols. It results from this condition that the user must learn for each of the 36 symbols (letters and ciphers) the configuration prescribed by the manufacturer of the device, where each symbol is written on at least part of 14 electrodes. Such a data input is impracticable for an average person.